A Labour government will reform, rather than defend uncompetitive markets, but help industry to build a skilled labour force, Ed Miliband has said.

In a speech to a business audience, the Labour leader attempted to balance his commitment to changing capitalism while still nourish entrepreneurship.

He said: "I would be a prime minister who champions the rights of the consumer and the rights of businesses to succeed and make profits in a competitive market at the same time."

Miliband said his five goals were to restore that trust in Britain's institutions, create a skilled workforce, implement an industrial policy for good private-sector jobs in every region of Britain, support a culture of long-termism and reform the financial markets so that they work in the public interest.

He was speaking at a packed Imax cinema in the Science Museum, London, at an event that drew parallels with those organised by Tony Blair to woo the business community before the 1997 election.

Part of Labour's goal during its week of setting its industrial policy has been to try to show that much of its analysis of what is wrong in British industry is shared by some industrialists, bankers and policy-makers, and is not an anti-capitalist statist agenda.

Elsewhere at the conference, Lord Sainsbury said unacceptable business practices and rigged markets needed to be driven out, or "else the capitalist system will fall into disrepute". At the same time he said "successful entrepreneurs should be applauded, richly rewarded and treated like heroes".

Sainsbury also said politicians needed to be clearer about the budgets and roles they are willing to devolve to city regions and those that will remain at the centre. He said it would be a nonsense for instance for each 39 local enterprise partnerships to run their own life science policy.

Sir John Armitt, a former chairman of the Olympic Delivery Authority, vowed that his Miliband-endorsed plan for an independent national commission responsible for identifying Britain's long-term infrastructure needs was not taking the politics out of the issue. He said: "You cannot take the politics out of infrastructure, but you do need cross-party support."

Lord Adonis, a former Labour transport minister, said there was some cross-party consensus on industrial policy, but that there was also two casts of mind in politics: "One inactive and pessimistic about solving decades-old problems, and the other optimistic and full of the spirit of the great Victorians."

Miliband told a Q&A session that he was still sceptical about Heathrow airport expansion, but added that he would await the report from the Davies commission set up by government and due to report after the election. He made no commitment to accept the commission's findings.

But Miliband drew most applause when he made a strong case for an open UK within the EU. "I have no truck with those who say we should cut ourselves off from the rest of the world. Our focus must not be on drifting toward exit but on acting now to reform the European Union so it works for Britain. That means working with our allies to reform the things that aren't right: the budget, rules on immigration and benefits, and giving more powers to national parliaments."

His remarks represent an indirect repudiation of the Unite union, Labour's biggest financial backer which this week called for an unconditional in-out referendum on UK membership of the EU.

But Miliband also argued that the causes of the discontent about living standards "began before the recession and that's a very important clue for what we need to do as a country. Because, just as the problems began before the recession, so the solutions won't come from recovery alone. The challenge we face is to tackle these longstanding, deep-seated problems – that is the central mission I see for the government I want to lead in 10 months' time."

He then set out commitments on building all-party support for infrastructure spending, addressing the decades-long skills gap, and boosting innovation by supporting long-termism.

The Science Museum conference was organised by Ed Balls, the shadow chancellor, and Policy Network. It was in part designed to showcase Labour's approach to business that appeared in a series of little-read or publicised independent reports commissioned by Balls.

The attendance of Sainsbury, a former Labour science minister, and Lord Mandelson, a former industry secretary, suggests the sometimes sharp rhetorical differences within the party about how to address business are reconcilable.

It also reflects a growing dialogue between Mandelson and Balls, partly owing to agreements on how far reform of business and banking can be pushed before becoming too interventionist.

Terry Scuolar, head of the Engineering Employers Federation, backed Miliband's sentiments saying: "Overall, his speech will go some way towards reassuring industry that Labour understands the importance of supporting business.

"Most of the proposals outlined are positive, including an independent infrastructure authority, employer ownership of skills, improving access to finance for business and regional growth plans. We now want to see firm commitments on tax and spending and, where the resources for some of these commitments will come from as there will inevitably be a financial impact."